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1997年,东芝笔记本电脑率先在其TECRA 750DVD中选用了DVD驱动,推动笔记本电脑新的发展。DVD在存储、视听应用、音频方面部与CD-ROM有着显著的不同。虽然DVD盘片的外观和尺寸与现在广泛使用的CD盘片没有什么区别,但DVD盘片与CD盘片的结构是不同的。在CD盘上,纪录信息的最小凹凸坑长度为0.83um。各条光道间的间距为1.6um。而在DVD盘片的容量变成了CD盘片的7-20倍。为了进一步提高DVD盘片的存储容量,还采取了提高盘面利用率、减少纠错码长度、修改信号调制方式以及减少每个扇区字节数等措施,这使得DVD盘片的单面层容量高达4.7GB,是CD盘片容量的7倍多。由于DVD盘片的最小凹凸坑长度以及光道间距都比CD盘小得多,因此DVD的光拾取器(激光头)采用波长为625nm或650nm的短波长红色半导体激
In 1997, Toshiba notebook took the lead in its TECRA 750DVD selected DVD drive to promote the new development of notebook computers. DVD in storage, audio-visual applications, audio and CD-ROM has a significant difference. Although the appearance and size of DVD discs are not different from those of widely used CD discs, the structure of DVD discs and CD discs is different. On a CD, the minimum groove length for record information is 0.83um. The distance between each track is 1.6um. The capacity of the DVD disc into CD discs 7-20 times. In order to further improve the storage capacity of DVD disc, but also taken to improve disk utilization, reduce the length of error correction code, modify the signal modulation and reduce the number of bytes per sector and other measures, which makes DVD single-sided layer capacity Up to 4.7GB, is more than 7 times the capacity of CD discs. Since the minimum disc pit length and track pitch of a DVD disc are much smaller than that of a CD disc, an optical pickup (laser head) for DVD uses a short wavelength red semiconductor laser having a wavelength of 625 nm or 650 nm